Acids and bases, both organic and inorganic, are used routinely in research and clinical laboratories, and in industry. They are most often utilized in liquid form. Regardless of the care taken in handling, accidents resulting in spillage onto the work bench or surrounding environment are not entirely preventable. The caustic nature of many of the acids and bases used renders ordinary clean-up techniques ineffective, if not unsafe. In response, various products and methods have been developed for specifically dealing with chemical spills and, more specifically, spills involving acids and bases. There are limitations attendant to each of the methods and products currently available, however. None provide a method which can be instituted both rapidly and simply, using a product with a wide-spectrum of use for acid and base spills, which comprises a superabsorbent material, capable of localizing the spill during absorption, and a means for neutralizing the offensive chemical.
U.S. Pat. No. 4,840,734, issued to Edward R. Johnson on Jun. 20, 1989, discloses a product and process for absorbing liquid leaks and spills. The patent discloses that the product comprises a closed cell having a cell wall permeable to liquid. Within the cell is an inorganic, inert absorbent. The patent discloses that the absorbent is preferably selected from a number of inert inorganic materials which are capable of absorbing an excessive amount of liquid and that it is desirable to provide an absorbent which will neutralize chemicals which are otherwise reactive. Preferable absorbents listed include clay, vermiculite, perlite, diatomaceous earth, hydrous aluminum silicate, and calcium carbonate. The patent further discloses that, in the case of absorbing acidic spills, the cell wall material should be made of materials such as polyester or cotton terrycloth. Although the patent discloses that a neutralizing chemical may be contained within the interior of the cell wall, the absence of a neutralizing chemical in the cell wall itself presents a hazard to subsequent handlers, as well as upon ultimate disposal. This is particularly true in the instance where caustic acids or bases are absorbed since, with an enclosed cell, the handler's first impulse would be to pick up the cell and thereby come in direct contact with the caustic material. Additionally, the absorbent cell size is predetermined and is not tailored to the needs of a particular incident. Consequently, a cell may be too large or too small for a particular spill. Furthermore, no superabsorbent material is disclosed.
U.S. Pat. No. 4,769,084, issued to Hans-Erich Gubela on Sep. 6, 1988, discloses synthetic chemical absorbents. The invention disclosed is a phenol resin foamed plastic which has been milled into a powder or fine flakes, the grain size of which would preferably be between 0.5 and 2 mm. The patent discloses that, in one embodiment, the resin can be treated with a base or an acid in order to enable neutralization of an acid or base, respectively. The patent discloses that the resin works more by principles of adsorption, instead of absorption, being based upon the depositing of the material to be adsorbed on as many surfaces as possible. Alternate embodiments suggest that the resin be used as packing material. Because the disclosed method of action--adsorption--acts as a function of surface area contact with the spill, this invention appears most suited for the situation in which the adsorbent material could be completely immersed in the liquid to be adsorbed, as opposed to being dispensed on top of liquid which has been spilled. No superabsorbent material is disclosed.
U.S. Pat. No. 4,483,716, issued to Harold L. Heller on Nov. 20, 1984, discloses a poultice method for extracting hazardous spills. The patent discloses that the absorbent material enables the removal of chemicals spilled on porous surfaces. Prior to application to the spill, the components must be blended together to form a slurry or paste. The components include absorbent materials such as clay, silica, or calcium carbonate and a volatile solvent. The patent discloses that the composition may also contain a gelling agent to help maintain the slurry in position after application. As the slurry dries, it wicks the chemical up through the porous surface. Eventually, the slurry dries to a powder. The patent discloses that a detoxifying agent, such as sodium polyethylene glycol, can be incorporated into the composition. The focus of the patent, however, appears to be upon the detoxification of materials such as halogenated organic compounds and not acids or bases, nor is such an application suggested. Furthermore, the solvent requirement appears to limit the scope of use and ease of application since the patent discloses that the solvent must be chosen in accordance with the solubility characteristics of the spilled chemical. Additionally, if a detoxifying agent is employed, the solvent must be selected to be compatible with the detoxifying agent as well. The method of the patent is to be tailored to meet the chemistry requirements of a particular spill, as opposed to providing an absorbent with a wide spectrum of use. No superabsorbent material is disclosed.
U.S. Pat. No. 4,210,460, issued to James W. Seidenberger on Jul. 1, 1980, discloses a spill control composition and the use thereof. This patent is directed specifically to spills of hydrofluoric acid only. The composition comprises an aqueous solution of calcium acetate, powdered magnesia, and a pH indicator. The patent discloses that the calcium acetate solution is applied to the spill first, in a quantity usually at least seven times the estimated volume of the spilled acid. When a white precipitate is formed, the magnesium is brought into solution and then added to the spill composite. A slurry is then formed. The patent discloses that the method of the invention allows for a safe and effective means of cleaning up the hydrofluoric acid without excess evolution of heat and fumes. As such, the method is somewhat complex and time-consuming. No superabsorbent material is disclosed.
None of the art discussed above describes a method, or composition, which is both simple in application yet effective, and which enables clean-ups and disposals which are both quick and safe--i.e., provide a neutralizing agent and a superabsorbent material--for a wide-spectrum of acid and bases. Due to the foregoing, a method and composition which provides all of the aforementioned qualities and limits contact with the potential hazardous materials is urgently needed.